570 PHILOSOPHY OF ZOOLOGY. 



mid legs furnished with five joints, as in the preceding, but 

 the tarsi of the hind legs have only four joints. In a few 

 genera, as Rhinomacer, Rhinosimus, and Stenostoma, con- 

 stituting the family Rhinomaceridae, the front of the head 

 is advanced into a snout, on which are seated the antennae. 

 In the remaining genera, the front exhibits the usual cha- 

 racters. In some, the head is triangular, or heart-shaped, 

 and is furnished with a neck, and the maxillae have no cor- 

 neous tooth on their inner edge. Among these there are 

 some which have the claws simple, as the Pyrochroidae, 

 with bilobate tarsi, including the genera Pyrochroa, No- 

 toxus, Scraptia, and Dendrocera ; in the Mordelladas, in 

 which the tarsi of the hind legs at least are simple, are in- 

 cluded the Mordella, Rhipiphorus, Anapsis, Horea, and 

 Apalus. Among others, the claws are double, or deeply 

 divided. In the genus Tetraonix, the penultimate joint of 

 the tarsi is bilobate, in the others entire. In the Myla- 

 bridae, the antennae are thickened at the extremity, as in 

 Mylabris, Hycleus, Ccrocoma, while in the Cantharida?, 

 the antennas are of equal thickness throughout, or rather 

 taper towards the point, as Cantharis, Meloe, Zonites, and 

 Onas. 



Among those genera which have the head oval and des- 

 titute of a neck, there are some which have the maxillae 

 furnished with a corneous tooth on the inner side. The 

 elytra, in some, are free, and cover membranaceous wings, as 

 the Tenebroiondae, including Tenebrio, Opatrum, Cryp- 

 ticus, Sarrotrium, and Toxicum. In many other genera 

 the elytra are united, and the membranaceous wings are 

 nearly obliterated. Some of these have the maxillary pal- 

 pi filiform, with the last joint nearly cylindrical. The 

 Erodiusidae have the maxillae covered with the mcntum, 

 as Erodius and Pimelia. In the Scaurusidae, the base of 

 the jaws arc exposed, as Scaurus, Tagenia, Sepidium, Mo- 



